Energy Technology Data Exchange (ETDEWEB)

The Weyl-Wigner prescription for quantization on Euclidean phase spaces makes essential use of Fourier duality. The extension of this property to more general phase spaces requires the use of Kac algebras, which provide the necessary background for the implementation of Fourier duality on general locally groups. Kac algebras - and the duality they incorporate are consequently examined as candidates for a general quantization framework extending the usual formalism. Using as a test case the simplest non-trivial phase space, the half-plane, it is shown how the structures present in the complete-plane case must be modified. Traces, for example, must be replaced by their noncommutative generalizations - weights - and the correspondence embodied in the Weyl-Wigner formalism is no more complete. Provided the underlying algebraic structure is suitably adapted to each case, Fourier duality is shown to be indeed a very powerful ...

CERN Document Server

This essay aims to summarize the main physical features arising from a new supersymmetric theory of gravitation. Based on preliminary discussions about classical field theory, cosmology, algebra and group theory, and taking formal results and theoretical considerations in comparison with several contributions from great authors, present work deals with gravity inside the limits of a meta-field theory, that is, a non-quantized but consistent representation of supergravity, the supersymmetry between gravitons and gravitinos. The introduction of meta-fields furnishes an independent framework for the study of gravity despite of constraints of quantization, treating the supersymmetric partners as deterministic actors of gravitation and not simply probabilistic entities. I explain my belief that gravitational field, by its own nature, is not quantizable in the same foot as the other fields, what does not ...

Energy Technology Data Exchange (ETDEWEB)

The gravitational radiation produced by the big bang is calculated in order to provide a condition for the unification of the gravitational and electromagnetic forces. By analogy with electromagnetic radiation and under the assumption that gravity is also quantized, it is shown that matter would have decoupled from gravitational radiation at a time of approximately 10 to the -43rd sec and would have dominated it at 10 to the -17th sec. Furthermore, the theory predicts a background gravitational radiation temperature of 0.003 K which peaks at a wavelength of about 1 m, which may be detected by the comparison of the synchronization of clocks at increasing distances.

UK PubMed Central (United Kingdom)

BackgroundThe cachexia-anorexia syndrome impacts on patients' physical independence and quality of life. New treatments are required and need to be evaluated using acceptable and...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundThe widespread use of nutritional supplements among athletes is poorly understood. The prevalence of supplement intake and users' knowledge have been researched independently...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundExcessive television (TV) viewing might play an important role in the development of cardiovascular disease (CVD). The aim of this study was to examine the independent...Full Text Available

UK PubMed Central (United Kingdom)

Background:Erectile dysfunction in type-2 diabetes may be an independent marker for coronary artery disease. Present study was undertaken to investigate whether type-2 diabetic...Full Text Available

CERN Document Server

In this paper we prove the existence of isomorphisms between certain non-commutative algebras that are interesting from representation theoretic perspective and arise as quantizations of certain Poisson algebras. We show that quantizations of Kleinian resolutions obtained by three different constructions are isomorphic to each other. The constructions are via symplectic reflection algebras, quantum Hamiltonian reduction, and W-algebras. Next, we prove that parabolic W-algebras in type A are isomorphic to quantum Hamiltonian reductions associated to quivers of type A. Finally, we show that the symplectic reflection algebras for wreath-products of the symmetric group and a Kleinian group are isomorphic to certain quantum Hamiltonian reductions. Our results involving W-algebras are new, while for those dealing with symplectic reflection algebras we just give new proofs. A key ingredient in our proofs is the study of ...

British Library Electronic Table of Contents (United Kingdom)

Background: High satisfaction rates have been reported after autologous breast reconstruction. Yet, most mastectomy patients receive implant reconstructions (ImBR). Independent and active decision makers have shown mainly to choose for autologous reconstructions, such as the Deep inferior epigastric perforator (DIEP) flap (DiepBR). To further explore the decision making to opt for either ImBR or DiepBR, we investigated patient knowledge, informational resources used, effect of plastic surgeons' advice, coping style and personal independence. Methods: A total of 153 women, who were planned for DiepBR or ImBR preoperatively, completed a study-specific and standardised validated psychological questionnaire. Analyses were aimed at information-seeking behaviour, personal independence and coping...

Energy Technology Data Exchange (ETDEWEB)

The addition of a thermionic rf gun [1] and a photocathode rf gun will allow the Advanced Photon Source (APS) linear accelerator (linac) [2] [3] to become a free-electron laser (FEL) driver [4]. As the FEL project progresses, the existing high-charge DC thermionic gun will no longer be critical to APS operation and could be used to generate high-energy or low-energy electrons to drive a slow-positron source. We investigated possibilities to create a useful low-energy source that could operate semi-independently and would have a low neutron background.

Energy Technology Data Exchange (ETDEWEB)

The non-perturbative validity of covariant BRST-quantization of gauge theories on compact Euclidean space-time manifolds is reviewed. BRST-quantization is related to the construction of a Topological Quantum Field Theory (TQFT) of Witten type on the gauge group. The criterion for the non-perturbative validity of the quantization is that the partition function of the corresponding TQFT does not vanish and that its (equi-variant) BRST-algebra is free of anomalies. I sketch the construction of a TQFT whose partition function is proportional to the generalized Euler-characteristic of the coset space S U (n){sub gauge} / SU(n){sub global} with an associated equi-variant BRST-algebra that manifestly preserves translational symmetry. Some non-perturbative consequences of this approach are discussed. (author)

Energy Technology Data Exchange (ETDEWEB)

The MiniBooNE Collaboration reports first results of a search for {upsilon}{sub e} appearance in a {upsilon}{sub {mu}} beam. With two largely independent analyses, we observe no significant excess of events above background for reconstructed neutrino energies above 475 MeV. The data are consistent with no oscillations within a two neutrino appearance-only oscillation model.

CERN Document Server

A phase transition of gas-liquid type with an upper critical point is examined which arises in a model of charges of one sign on compensating background (OCP). The phase transition parameters are dependent on the detailed assumptions about the compressibility of the background, but the occurrence of this transition is independent on the background equation of state. In the electron-gas model ('jellium'), this transition appears to rule out Wigner crystallization. A variational principle in statistical mechanics is used to derive so-called Double-OCP model for a superposition of two one-component plasma models for charges of opposite sign. The free energy of this model sets an upper bound to that of a real plasma. Situations are discussed where this transition should manifest itself in anomalies in the approximate description of a non-ideal plasma.

International Nuclear Information System (INIS)

Lorentz invariant theory of second quantization of superluminal electromagnetic fields has been constructed in purely group theoretical manner by using the reduced expansion of four-vector fields for imaginary mass system in terms of standard helicity representations of Poincare group. It has been shown that the usual relationship of spin and statistics need not be inverted for Lorentz invariance of the theory of spin-1 tachyons. (author).

Energy Technology Data Exchange (ETDEWEB)

This thesis investigates the application of artificial neural networks for the compression of image data. An algorithm is developed using the competitive learning paradigm which takes advantage of the parallel processing and classification capability of neural networks to produce an efficient implementation of vector quantization. Multi-Stage, tree searched, and classification vector quantization codebook design are adapted to the neural network design to reduce the computational cost and hardware requirements. The results show that the new algorithm provides a substantial reduction in computational costs and an improvement in performance.

Energy Technology Data Exchange (ETDEWEB)

An algebraic formulation of the electromagnetic field in which various quantization procedures can be described was chosen to discuss perturbation calculations. It is shown that the Feynman rules and the second order calculation of the self-energy of the electron can be developed on the basis of the Fermi method of quantization. The algebraic approach clarifies the problems in defining the vacuum and other states which are associated with calculations in terms of field algebra operators. It is demonstrated that the vacuum state defined on the field algebra by Schwinger leads to incorrect results in the self-energy calculation.

British Library Electronic Table of Contents (United Kingdom)

Background.There are no suitably powered epidemiological studies of `transient azotaemia' (TA). The objective of this study was to describe the epidemiology of TA and its independent association with hospital mortality. We hypothesized that TA would be associated with an independent increase in the risk of death. Methods.We retrospectively studied all patients admitted to a university-affiliated hospital in Australia between January 2000 and December 2002. Patients were excluded if they were <15 years old, were on chronic dialysis, had kidney transplant or if their length of hospital stay was <24 hours. We defined TA as rapidly recovering acute kidney injury (AKI) (return to no-AKI risk, injury, failure, loss, end stage (RIFLE) class within 72 hours of onset). We performed descriptive and ...

British Library Electronic Table of Contents (United Kingdom)

Abstract Background: Obstructive sleep apnea (OSA), a highly prevalent condition, is independently associated with increased risks of developing type 2 diabetes mellitus (T2D) and metabolic syndrome. It is unclear, however, if the severity of OSA has any impact on glycemic control among patients with T2D. We therefore aimed to determine the independent association between OSA severity and glycosylated hemoglobin (HbA1c) in patients with T2D. Methods: This was an observational cross-sectional study of 52 consecutive patients attending the diabetes obesity clinic between January 2008 to February 2010 with risk factors for sleep apnea and who underwent polysomnography study. Clinical, demographic, and lifestyle data were recorded using a questionnaire. Results: Prevalence of OSA in this clini...

International Nuclear Information System (INIS)

This report is the result of field work performed at the former White Point Nike Missile Site, San Pedro, California. The Hazardous Waste Remedial Actions Program tasked the Oak Ridge National Laboratory Pollutant Assessments Group in Grand Junction, Colo., with this project. The objective was to determine whether or not radioisotopes possibly associated with past Department of Defense (DOD) operations were present and within accepted background levels. The radiation survey was accomplished by performing three independent radiation surveys, both outdoors and indoors, and random soil sampling. Initially, the site was land surveyed to develop a grid block system. A background radiation investigation was performed out in the San Pedro area.

British Library Electronic Table of Contents (United Kingdom)

Background Atrial fibrillation (AF) is the most common sustained atrial arrhythmia and it is independently associated with an increased morbidity and mortality. As a result of the high prevalence of AF, the economic and clinical impact of the disease is substantial. This study describes the economic and clinical impact of AF in the Netherlands. Methods Epidemiological data on AF in the Netherlands were projected on population estimates of the Netherlands in 2009 and combined with data on the cost of AF and its interventions. Results Overall prevalence of AF in the Netherlands is 5.5% in the population over 55?years, corresponding to about 250,000 AF patients. The prevalence increases with age, and the mean age of AF patients is 69.3?years. Incidence of AF in the Netherlands varies with age...

Energy Technology Data Exchange (ETDEWEB)

The phase space of quantized systems that contain tachyons has been investigated. Interpretation difficulties and unexpected divergences are found when we consider the volume of Lorentz-invariant phase space. These problems can be overcome, however, at the expense of Lorentz invariance.

International Nuclear Information System (INIS)

We consider the integrable structure of the quantum lattice W_N algebras. We introduce the ultralocal Lax matrix, and show that the Yang-Baxter relation is satisfied with a Z_N invariant R-matrix. (orig.).

CERN Document Server

This paper describes an effective unsupervised speaker indexing approach. We suggest a two stage algorithm to speed-up the state-of-the-art algorithm based on the Bayesian Information Criterion (BIC). In the first stage of the merging process a computationally cheap method based on the vector quantization (VQ) is used. Then in the second stage a more computational expensive technique based on the BIC is applied. In the speaker indexing task a turning parameter or a threshold is used. We suggest an on-line procedure to define the value of a turning parameter without using development data. The results are evaluated using 10 hours of audio data.

Energy Technology Data Exchange (ETDEWEB)

The penetrance of Leber's hereditary optic neuropathy (LHON) in families with primary mitochondrial DNA (mtDNA) mutations is very complex. Matrilineal and nuclear genetic background, as well as environmental factors, have been reported to be involved in different affected pedigrees. Here we describe two large Chinese families that show a striking difference in the penetrance of LHON, in which 53.3% and 15.0% of members were affected (P < 0.02), respectively. Analysis of the complete mtDNA genome of the two families revealed the presence of the primary mutation G11778A and several other variants suggesting the same haplogroup status G2a. The family with higher penetrance contained a previously described secondary mutation G13708A, which presents a polymorphism in normal Chinese samples and does not affect in vivo mitochondrial oxidative metabolism as described in a previous study. Evolutionary analysis failed to indicate any putatively pathogenic ...

British Library Electronic Table of Contents (United Kingdom)

Background: Ecchymosis, oedema, haematoma and pain after SMAS-based facelift surgery are all the direct result of the physical trauma of surgery and subsequent inflammatory response. Hilotherapy is a novel form of cryotherapy that purports to minimise these events through single-use face masks circulating cooled, sterile water. This study was performed to assess the validity of Hilotherapy in this population of patients. Methods: Over 14 weeks fifty consecutive patients were randomised to post-operative facial cooling with Hilotherapy or management with standard dressings alone, while fifteen subsequent, consecutive patients were randomised to cooling of one side of the face but not the other. Assessment of ecchymosis, oedema, haematoma and pain was performed independently by clinical staf...

British Library Electronic Table of Contents (United Kingdom)

Background Experimental and clinical studies have identified a crucial role of microcirculation impairment in severe infections. We hypothesized that mottling, a sign of microcirculation alterations, was correlated to survival during septic shock. Methods We conducted a prospective observational study in a tertiary teaching hospital. All consecutive patients with septic shock were included during a 7-month period. After initial resuscitation, we recorded hemodynamic parameters and analyzed their predictive value on mortality. The mottling score (from 0 to 5), based on mottling area extension from the knees to the periphery, was very reproducible, with an excellent agreement between independent observers [kappa?=?0.87, 95% CI (0.72?0.97)]. Results Sixty patients were included. The SOFA scor...

British Library Electronic Table of Contents (United Kingdom)

Background Identifying susceptibility genes for endophenotypes by studying analogous behaviors across species is an important strategy for understanding the pathophysiology underlying psychiatric disorders. This approach provides novel biological pathways plus validated animal models critical for selective drug development. One such endophenotype is avoidance behavior. Methods In the present study, novel automated registration methods for longitudinal behavioral assessment in home cages are used to screen a panel of recently generated mouse chromosome substitution strains that are very powerful in quantitative trait loci (QTL) detection of complex traits. In this way, we identified chromosomes regulating avoidance behavior (increased sheltering preference) independent of motor activity lev...

Energy Technology Data Exchange (ETDEWEB)

Concerning the gamma emitters, the only analysis on soils put in evidence the presence of cesium-137 ({sup 137}Cs), that does not come from the cyclotron functioning but from past man action as the Chernobylsk accident and the nuclear weapon tests in atmosphere. Independently of the functioning of the installation, we observe an increase of the ambient gamma radiation only near radioactive waste storage. It results of the storage of the former cyclotron elements. The induced increase is moderated because at 5 meters the values do not exceed the background noise. In relation with the functioning of the installation an increase of the ambient gamma radiation is noticed. Two causes are to considered: the release of radionuclides in atmosphere with gaseous effluents and the radiance of radiation sources inside the building. After the stopping of the installation (48 h at least), no increase of gamma radiation is observed. About the neutrons ...

International Nuclear Information System (INIS)

The static magnetization of solid "3He contained in sintered copper was measured. The results of the density on the melting curve show that below 5 mK, the magnetization M rises above the Curie-Weiss law extrapolated from high temperature. It reaches a maximum of twice as much as the Curie Weiss law value at temperature Tm, which would be somewhat below 1.25 mK if the system could be warmed up at infinitesimally slow rate. Below Tm, M decreases rapidly to 0.4 of its maximum, then appears to become independent of temperature. The previously reported decrease of specific heat below the Curie-Weiss law value in the range below 4 mK is apparently related to the increase of M in that range. At the low temperature end, apparent decrease of M is due to the fact that there is background magnetization which is out of equilibrium with the thermometer when there is solid "3He in the sample cell. It is suspected that the background ...

International Nuclear Information System (INIS)

A quantum mechanical analysis of the guided light in integrated photonics waveguides is presented. The analysis is made starting from one-dimensional (1D) guided vector modes by taking into account the modal orthonormalization property on a cross section of an optical waveguide, the vector structure of the guided optical modes and the reversal-time symmetry in order to quantize the 1D vector modes and to derive the quantum momentum operator and the Heisenberg equations. The results provide a quantum-consistent formulation of the linear and nonlinear quantum light propagations as a function of forward and backward creation and annihilation operators in integrated photonics. As an illustration, an application to an integrated nonlinear directional coupler is given, that is, both the nonlinear momentum and the Heisenberg equations of the nonlinear coupler are derived.

British Library Electronic Table of Contents (United Kingdom)

In this paper, we develop a batch fuzzy learning vector quantization algorithm that attempts to solve certain problems related to the implementation of fuzzy clustering in image compression. The algorithm's structure encompasses two basic components. First, a modified objective function of the fuzzy c-means method is reformulated and then is minimized by means of an iterative gradient-descent procedure. Second, the overall training procedure is equipped with a systematic strategy for the transition from fuzzy mode, where each training vector is assigned to more than one codebook vectors, to crisp mode, where each training vector is assigned to only one codebook vector. The algorithm is fast and easy to implement. Finally, the simulation results show that the method is efficient and appears...

Energy Technology Data Exchange (ETDEWEB)

The wave equation of a spinless tachyon is studied in Schwarzschild space-time. In contrast to earlier approaches to the problem, it is shown that tachyonic static solutions satisfy a simple second-order linear differential equation regardless of the mass of the black hole and the mass parameter of the tachyon. Physical implication of the present approach is discussed. Using Langer modification of the WKB (Wentzel-Kramers-Brillouin) boundary condition an expression similar to the Bohr-Sommerfeld quantization condition is derived.

CERN Document Server

Canonical gravity in real Ashtekar-Barbero variables is generalized to allow for fermionic matter. The resulting torsion changes several expressions in Holst's original vacuum analysis, which are explicitly displayed here. This in turn requires adaptations to the known canonical (loop) quantization of gravity coupled to fermions, which is discussed on the basis of the classical analysis.

CERN Document Server

We study local radiation magnetohydrodynamic instabilities in static, optically thick, vertically stratified media with constant flux mean opacity. We include the effects of vertical gradients in a horizontal background magnetic field. Assuming rapid radiative diffusion, we use the zero gas pressure limit as an entry point for investigating the coupling between the photon bubble instability and the Parker instability. Apart from factors that depend on wavenumber orientation, the Parker instability exists for wavelengths longer than a characteristic wavelength lambda_{tran}, while photon bubbles exist for wavelengths shorter than lambda_{tran}. The growth rate in the Parker regime is independent of the orientation of the horizontal component of the wavenumber when radiative diffusion is rapid, but the range of Parker-like wavenumbers is extended if there exists strong horizontal shear between field lines (i.e. horizontal wavenumber perpendicular ...

Energy Technology Data Exchange (ETDEWEB)

The Electrochemical Technology Program at Argonne National Laboratory (ANL) provides advanced battery R D; technology transfer to industry; technical analyses, assessments, modeling, and databases; and independent testing and post-test analyses of advanced batteries. These capabilities and services are being offered to the US Advanced Battery Consortium (USABC) and Cooperative Research and Development Agreements (CRADA) are being negotiated for USABC-sponsored work at ANL. A small portion of DOE's cost share for USABC projects has been provided to ANL to continue R D and testing activities on key technologies that were previously supported directly by DOE. This report summarizes progress on these USABC projects during the period of April I through September 30, 1992. In this report, the objective, background, technical progress, and status are described for each task. The work is organized into the following task areas: 1.0 ...

Energy Technology Data Exchange (ETDEWEB)

A systematic study of non-perturbative quantum structure of the massive light-front Schwinger model and QED(3+1) in the continuum formulation is outlined. The light-front Hamiltonian and field algebra are derived in the Weyl gauge using the Dirac-Bergmann constrained quantization. Unitary transformation to the light-cone gauge representation is performed and the gauge-invariant fermi field is constructed. The importance of the Schwinger term in the current-current commutation relations for the derivation of the fermionic vacuum structure and bosonization in two dimensions is indicated.

International Nuclear Information System (INIS)

The problems associated with treating tachoyons in quantum field theory are discussed, and the quantization proposed by Arons and Sudarshan is chosen as the most satisfactory of the presently available methods, although it is unable to describe interactions in its present form. In order to help determine whether suitable S-matrices can ever be found, a perturbation-type expansion for the S-matrix is considered. It is shown that if the first order term is any polynomial in the tachyon field and its conjugate, then the reinterpreted, or physical, S-matrix will violate unitarity. An example shows that the inclusion of derivatives of the field is also expected to produce non-unitary physical S-matrices. The indications are that a correct interesting theory of tachyons must be non-local.

DEFF Research Database (Denmark)

We propose to encode a register of quantum bits in different collective electron spin wave excitations in a solid medium. Coupling to spins is enabled by locating them in the vicinity of a superconducting transmission line cavity, and making use of their strong collective coupling to the quantized radiation field. The transformation between different spin waves is achieved by applying gradient magnetic fields across the sample, while a Cooper pair box, resonant with the cavity field, may be used to carry out one- and two-qubit gate operations.

Energy Technology Data Exchange (ETDEWEB)

This monograph gives a detailed and pedagogical account of the geometry of rigid superspace and supersymmetric Yang-Mills theories. While the core of the text is concerned with the classical theory, the quantization and anomaly problem are briefly discussed following a comprehensive introduction to BRS differential algebras and their field theoretical applications. Among the treated topics are invariant forms and vector fields on superspace, the matrix-representation of the super-Poincare group, invariant connections on reductive homogeneous spaces and the supermetric approach. Various aspects of the subject are discussed for the first time in textbook and are consistently presented in a unified geometric formalism.

KoreaScience (Korea)

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Purpose: Hormonal stimulation can induce background enhancement (BE) in MR mammography (MRM). This fact has been assumed to decrease the accuracy of MRM. Consequently, this report investigates: 1. The prevalence of BE in postmenopausal vs. premenopausal women in correlation to hormonal cycle phase (CP). 2. The impact of hormonal status (HS) and BE on diagnostic accuracy. Materials and Methods: Consecutive patients over 22 months with complete HS information (week of CP or postmenopausal) were included in this prospective investigation. Exclusion criteria were any hormonal therapy, hysterectomy as well as cancer proven by biopsy. The standard of reference was histopathology. All MRM scans were acquired using the same protocol (1.5 T, dynamic T 1w GRE after 0.1 mmol/kg bw Gd-DTPA i. v.). Two radiologists rated all examinations in consensus according to BI-RADS. BE was defined as: 0 = missing, 1 = moderate, 2 = distinct. Results: 224 patients (150 postmenopausal, 74 ...

UK PubMed Central (United Kingdom)

Synthetic polypeptide antigens of L amino acids, although bearing repeating sequences, are thymus-dependent (L-TD), whereas the same polymers composed of D amino acids are thymus-independent (D-TI),...Full Text Available

Science.gov (United States)

... surprise. During Operation Goodwood, the British attempt to break out of their bridgeheads in Normandy, aBritish column was ...

Science.gov (United States)

disciplinary methods were used to independently determine the aerodynamic loads, the thermal response, and strardural performance of the hydrogen cooled ...

Science.gov (United States)

... While the large tanks served to regulate the water temper- ature, the polypropylene aquaria served as independent experimental units. ...

Science.gov (United States)

No abstract available.

CERN Document Server

Properties of a two-level atom coupled to the quantized electromagnetic field at finite temperature are studied. The analysis is based on a new method (inspired by QED) of describing qubits, developed previously by us at zero temperature (Phys. Rev. A 76, 062106 (2007)). In this paper, we make a generalization to finite temperature by introducing the Matsubara formalism and the temperature propagators. We analyze the spectral properties of different types of propagators and we derive a direct connection between the temperature propagators and the real time propagators. To show the effectiveness of this method, we calculate the temperature dependence of the polarizability of a two-level atom in the lowest order of perturbation theory and we predict an unexpected sharpness in the resonance behavior. The whole discussion is carried out without making the rotating wave approximation.

CERN Document Server

We study general two-dimensional sigma-models which do not possess manifest Lorentz invariance. We show how demanding that Lorentz invariance is recovered as an emergent on-shell symmetry constrains these sigma-models. The resulting actions have an underlying group-theoretic structure and resemble Poisson--Lie T-duality invariant actions. We consider the one-loop renormalization of these models and show that the quantum Lorentz anomaly is absent. We calculate the running of the couplings in general and show, with certain non-trivial examples, that this agrees with that of the T-dual models obtained classically from the duality invariant action. Hence, in these cases solving constraints before and after quantization are commuting operations.

International Nuclear Information System (INIS)

The Lorentz and coordinate covariant calculus of spinors in Riemannian spacetime, which is the mathematical model for the description of the quantum mechanics of elementary particles with spin interacting with the classical gravitation field, is explored. The Dirac equation describing the interaction of neutrinos with the gravitational fields of the Robertson-Walker cosmological world models is separated, and the spectrum of eigenfunctions and eigenvalues for particular choices of the set of quantum numbers is given explicitly for the k = 0 and k = +1 models, although only the radial equations determining the final quantum number are given for the k = -1 model. The mathematical theory of the motion of a perfect fluid whose elements interact via long-range neutrino-exchange forces, as well as gravitationally, is developed. The formalism for calculating, by calculating the Bogoliubov transformation of the Fock space operators that instantaneously diagonalize their ...

Energy Technology Data Exchange (ETDEWEB)

The development of nano/molecular devices will require atomic-sized electrical contacts or nano metric conductors for wiring. As metal nano wires exhibit quantized conductance at room temperature, quantum transport effects will play an important role in the practical implementation of nano devices. As copper is currently used as interconnecting metal in standard microelectronics, the characterization of Cu nano wire properties deserves special attention. In this work, we show a detailed study of structural and electronic properties of atomic-sized Cu wires. In particular, we have established a complete correlation between the conductance and the structure by associating real-time atomic resolution transmission electron microscopy imaging with molecular dynamic simulations, conductance measurements and conductance calculations. Our study has revealed the structural relaxation of Cu wires forming a pentagonal atomic arrangement along the [110] direction that allows a ...

CERN Document Server

In this paper we examine the relationship between covariance and unitarity for quantum gravity in Ashtekar variables. A usual description would discard half of the original Lorentz group, in exchange for the resulting simplifications of general relativity. We start by quantizing a trivial SL(2,C) gauge theory resulting in a nonunitary covariant theory. By the addition of a total time derivative we transform this into a unitary theory of the Ashtekar description of gravity with complete accountability of the degrees of freedom. We find that covariance on the spacetime level bears a direct relationship to covariance on the level ofthe quantum fields themselves. This procedure can in principle be applied to any totally constrained system, and bears a resemblance to the Gupta--Bleuler method. Finally, we make some observation regarding the loop representation of the SL(2,C) connection.

CERN Document Server

The effective approach to quantum dynamics allows a reformulation of the Dirac quantization procedure for constrained systems in terms of an infinite-dimensional constrained system of classical type. For semiclassical approximations, the quantum constrained system can be truncated to finite size and solved by the reduced phase space or gauge-fixing methods. In particular, the classical feasibility of local internal times is directly generalized to quantum systems, overcoming the main difficulties associated with the general problem of time in the semiclassical realm. The key features of local internal times and the procedure of patching global solutions using overlapping intervals of local internal times are described and illustrated by two quantum mechanical examples. The choice of time is tantamount to a choice of gauge at the effective level and changing the clock is, therefore, equivalent to a gauge transformation. This article complements the conceptual ...

Science.gov (United States)

We report the characteristics of visible vertical cavity surface emitting laser diodes. Wafers are grown such that the Fabry--Perot resonance wavelength changes with position from 690 to 620 nm, overlapping to varying degrees with the [ital n]=1 and [ital n]=2 quantum well gain peaks at [similar to]670 and 650 nm. Gain guided devices are tested across the entire wafer, and pulsed room temperature lasing is observed from 634.6 to 663.2 nm. Our results suggest that gain contributions from the second quantized state are required to overcome high cavity losses in order to achieve lasing.

Energy Technology Data Exchange (ETDEWEB)

Since information has been regarded os a physical entity, the field of quantum information theory has blossomed. This brings novel applications, such as quantum computation. This field has attracted the attention of numerous researchers with backgrounds ranging from computer science, mathematics and engineering, to the physical sciences. Thus, we now have an interdisciplinary field where great efforts are being made in order to build devices that should allow for the processing of information at a quantum level, and also in the understanding of the complex structure of some physical processes at a more basic level. This thesis is devoted to the theoretical study of structures at the nanometer-scale, 'nanostructures', through physical processes that mainly involve the solid-state and quantum optics, in order to propose reliable schemes for the processing of quantum information. Initially, the main results of quantum information theory and quantum ...

DEFF Research Database (Denmark)

OBJECTIVE: To evaluate the interobserver agreement of ultrasonographic assessment of finger and toe joints in patients with rheumatoid arthritis (RA) by 2 investigators with different medical backgrounds. METHODS: Ultrasonography and clinical examination were performed on 150 small joints of 30 patients with active RA. A General Electric LOGIQ 500 ultrasound unit with a 7-13-MHz linear array transducer was used. In each patient, 5 preselected small joints (second and third metacarpophalangeal, second proximal interphalangeal, first and second metatarsophalangeal) were examined independently on the same day by 2 ultrasound investigators (an experienced musculoskeletal radiologist and a rheumatologist with limited ultrasound training). Joint effusion, synovial thickening, bone erosions, and power Doppler signal were evaluated in accordance with an introduced 4-grade semiquantitative scoring system, on which the investigators had reached consensus ...

Energy Technology Data Exchange (ETDEWEB)

The study of audible noise from high voltage transmission lines and a high voltage transformer station was conducted in three parts. Part 1 consisted of long-term measurement and statistical analysis by computer reduction of audible noise as a result of corona discharge from high voltage transmission lines and the associated weather conditions which contribute to this noise. Recommendations are given concerning further computer programming in order to improve the statistical reliability of corona noise presence and reduce the degree of background noise contamination of the present results. Part 2 consisted of categorizing and cataloguing of corona noise spectra from long-term measurements on 550, 735 and 765 kV transmission lines and to provide a library of such sounds on magnetic tape to be used in the ongoing study of corona noise. Twenty-five different corona sound spectra have been identified and documented in a tape library. Average weather conditions ...

Science.gov (United States)

... Pagination or Media Count : 4. Abstract : The Support Battalion, 3rd Brigade, 82nd Airborne Division was visited on 7 December 1968. ...

UK PubMed Central (United Kingdom)

In response to stress, cells start transcriptional and transcription-independent programs that can lead to adaptation or death. Here, we show that multiple inducers of autophagy, including nutrient...Full Text Available

Science.gov (United States)

... adverse events and potential major events. 3.2.2.4 Clinical Events Committee (CEC) The independent CEC (cardiologists and neurologists ...

UK PubMed Central (United Kingdom)

In establishing a chronic haemodialysis unit in Brunei the difficulties encountered were less insuperable than had been expected. Quite unsophisticated patients successfully dialysed unattended in...Full Text Available

CERN Document Server

Entanglement swapping allows to establish entanglement between independent particles that never have interacted nor share a common past. This feature makes it an integral constituent of quantum repeaters and a promising tool for future tests of the foundations of quantum physics. Here, we demonstrate entanglement swapping with time-synchronized independent sources with a fidelity high enough to violate a Clauser-Horne-Shimony-Holt (CHSH) inequality by more than four standard deviations. The fact that both entangled photon pairs are created by fully independent laser sources, which are only electronically connected, ensures that this technique is suitable for future long-distance entanglement swapping and quantum-repeater experiments.

UK PubMed Central (United Kingdom)

Eukaryotes may influence pollutant degradation processes in groundwater ecosystems by activities such as predation on bacteria and recycling of nutrients. Culture-independent community profiling and...Full Text Available

UK PubMed Central (United Kingdom)

Prolonged disability is best understood as an illness that exists independently of the initiating disease. The disabled individual goes through predictable stages of disability before resolution occurs....Full Text Available

Science.gov (United States)

... Our primary work to date in this area has been with the Automated Transport and Retrieval System (ATRS) [1]. ATRS enables independent mobility ...

UK PubMed Central (United Kingdom)

BackgroundThis study investigated the knowledge of depression and preference for professional help, medications and treatment methods among Australians of Chinese-speaking background,...Full Text Available

Science.gov (United States)

ABSTRACT: BACKGROUND: The capacity to maintain internal ion homeostasis amidst changing conditions is particularly important for teleost fishes whose reproductive cycle is dependent upon movement from freshwater to seawater. Although the physiology of seawater osmoregulation in mitochondria-rich cells of fish gill epithelium is well understood, less is known about the underlying causes of inter- and intraspecific variation in salinity tolerance. We used a genome-scan approach in Arctic charr (Salvelinus alpinus) to map quantitative trait loci (QTL) correlated with variation in four salinity tolerance performance traits and six body size traits. Comparative genomics approaches allowed us to infer whether allelic variation at candidate gene loci (e.g., ATP1alpha1b, NKCC1, CFTR, and cldn10e) could have underlain observed variation. RESULTS: Combined parental analyses yielded genome-wide significant QTL on linkage groups 8, 14 and 20 for salinity tolerance performance ...

Energy Technology Data Exchange (ETDEWEB)

Background: Cu-diacetyl-bis(N{sup 4}-methylthiosemicarbazone) [Cu-ATSM], although excellent for oncology applications, may not be suitable for delineating cardiovascular or neurological hypoxia. For this reason, new Cu hypoxia positron emission tomography (PET) imaging agents are being examined to search for a higher selectivity for hypoxic or ischemic tissue at higher oxygen concentrations found in these tissues. Two approaches are to increase alkylation or to replace the sulfur atoms with selenium, resulting in the formation of selenosemicarbazones. Methods: Three {sup 64}Cu-labeled selenosemicarbazone complexes were synthesized and one was screened for hypoxia selectivity in vitro using EMT-6 mouse mammary carcinoma cells. Rodent biodistribution and small animal PET images were obtained from BALB/c mice implanted with EMT-6 tumors. One alkylated thiosemicarbazone was synthesized and examined. Results: Of the three bis(selenosemicarbazone) ligands synthesized and ...

UK PubMed Central (United Kingdom)

BackgroundA large and increasing part of the European population has a history of migration. Germany, for example, is home to about 15 million people with migrant background, which...Full Text Available

CERN Document Server

The structure of Poisson polynomial algebras of the type obtained as semiclassical limits of quantized coordinate rings is investigated. Sufficient conditions for a rational Poisson action of a torus on such an algebra to leave only finitely many Poisson prime ideals invariant are obtained. Combined with previous work of the first-named author, this establishes the Poisson Dixmier-Moeglin equivalence for large classes of Poisson polynomial rings, such as semiclassical limits of quantum matrices, quantum symplectic and euclidean spaces, quantum symmetric and antisymmetric matrices. For a similarly large class of Poisson polynomial rings, it is proved that the quotient field of the algebra (respectively, of any Poisson prime factor ring) is a rational function field $F(x_1,...,x_n)$ over the base field (respectively, over an extension field of the base field) with $\\{x_i,x_j\\}= \\lambda_{ij} x_ix_j$ for suitable scalars $\\lambda_{ij}$, thus establishing a ...

Energy Technology Data Exchange (ETDEWEB)

The canonical quantum theory of gravity-quantum geometrodynamics (QG)-is applied to the homogeneous Bianchi type IX cosmological model. As a result, a framework for the quantum theory of homogeneous cosmologies is developed. We show that the theory is internally consistent and prove that it possesses the correct classical limit (the theory of general relativity). To emphasize the special role that the constraints play in this new theory, we compare it to the traditional ADM square-root and Wheeler-DeWitt quantization schemes. We show that, unlike traditional approaches, QG leads to a well-defined Schroedinger equation for the wavefunction of the universe that is inherently coupled to the expectation value of the constraint equations. This coupling to the constraints is responsible for the appearance of a coherent spacetime picture. Thus, the physical meaning of the constraints of the theory is quite different from Dirac's interpretation. In light of this ...

CERN Document Server

This thesis consists of three parts. In the first part we review the quantization of Yang-Mills theories and perturbative quantum gravity in curved spacetime. In the second part we calculate the Feynman propagators of the Faddeev-Popov ghosts for Yang-Mills theories and perturbative quantum gravity in the covariant gauge. In the third part we investigate the physical equivalence of covariant Wightman graviton two-point function with the physical graviton two-point function. The Feynman propagators of the Faddeev-Popov ghosts for Yang-Mills theories and perturbative quantum gravity in the covariant gauge are infrared (IR) divergent in de Sitter spacetime. We point out, that if we regularize these divergences by introducing a finite mass and take the zero mass limit at the end, then the modes responsible for these divergences will not contribute to loop diagrams in computations of time-ordered products in either Yang-Mills theories or perturbative quantum gravity. We ...

Energy Technology Data Exchange (ETDEWEB)

Target recognition requires the ability to distinguish targets from non-targets, a capability called one-class generalization. Many neural network pattern classifiers fail as one-class classifiers because they use open decision boundaries. To function as one-class classifier, a neural network must have three types of generalization: within-class, between-class, and out-of-class. We discuss these three types of generalization and identify neural network architectures that meet these requirements. We have applied our one-class classifier ideas to the problem of automatic target recognition in synthetic aperture radar. We have compared three neural network algorithms: Carpenter and Grossberg`s algorithmic version of the Adaptive Resonance Theory (ART-2A), Kohonen`s Learning Vector Quantization (LVQ), and Reilly and Cooper`s Restricted Coulomb Energy network (RCE). The ART 2-A neural network gives the best results, with 100% within-class, between-class, and ...

Science.gov (United States)

We investigate the form factors of the chiral-odd nucleon matrix element of the tensor current. In particular, we aim at the anomalous tensor magnetic form factors of the nucleon within the framework of the SU(3) and SU(2) chiral quark-soliton model. We consider 1/N{sub c} rotational corrections and linear effects of SU(3) symmetry breaking with the symmetry-conserving quantization employed. We first obtain the results of the anomalous tensor magnetic moments for the up and down quarks: {kappa}{sub T}{sup u}=3.56 and {kappa}{sub T}{sup d}=1.83, respectively. The strange anomalous tensor magnetic moment is yielded to be {kappa}{sub T}{sup s}=0.2{approx}-0.2, that is compatible with zero. We also calculate the corresponding form factors {kappa}{sub T}{sup q}(Q{sup 2}) up to a momentum transfer Q{sup 2{<=}}1 GeV{sup 2} at a renormalization scale of 0.36 GeV{sup 2}.

Energy Technology Data Exchange (ETDEWEB)

This article examines the developing market for independent power projects in Canada. The topics of the article include bidding in Ontario, the Quebec market, powering British Columbia, and market forces at work in Canada. Discussed are current projects in all stages of completion from bidding to production and includes gas-fired cogeneration, gas-fired combined-cycle electricity generation and cogeneration, wood-waste fired plants, repowering of existing utility plants, and hydroelectric power plants.

International Nuclear Information System (INIS)

The time-dependent probability distribution of neutrons, precursors and detectrons in a space-independent, low-power, multiplying assembly with a source is developed in the multigroup approximation as forward and backward Kolmogorov equations. The relationship between these as adjoint equations is made explicit in a tensor notation and the equations developed in the generating-function formalism. (author).

ScienceCinema

...global warming situation is more than evaporation around ...background red ? which was the global warming the ...

Energy Technology Data Exchange (ETDEWEB)

A stochastic wind simulation for VAWTs (VSTOC) has been developed which yields turbulent wind-velocity fluctuations for rotationally sampled points. This allows three-component wind-velocity fluctuations to be simulated at specified nodal points on the wind-turbine rotor. A first-order convection scheme is used which accounts for the decrease in streamwise velocity as the flow passes through the wind-turbine rotor. The VSTOC simulation is independent of the particular analytical technique used to predict the aerodynamic and performance characteristics of the turbine. The VSTOC subroutine may be used simply as a subroutine in a particular VAWT prediction code or it may be used as a subroutine in an independent processor. The independent processor is used to interact with a version of the VAWT prediction code which is segmented into deterministic and stochastic modules. Using VSTOC in this fashion is very efficient with ...

UK PubMed Central (United Kingdom)

The network of coupled neurons in the pre-Bötzinger complex (pBC) of the medulla generates a bursting rhythm, which underlies the inspiratory phase of respiration. In some of these neurons,...Full Text Available

UK PubMed Central (United Kingdom)

SUMMARYThe cytolytic activity of natural killer (NK) cells is regulated by inhibitory receptors that detect the absence of self molecules on target cells. Structural studies of...Full Text Available

UK PubMed Central (United Kingdom)

[1] Independent data from the Gulf of Mexico are used to develop and test the hypothesis that the same sequence of physical and ecological events each year allows the toxic dinoflagellate Karenia...Full Text Available

UK PubMed Central (United Kingdom)

BACKGROUNDProtocadherin-PC (PCDH-PC) expression is upregulated in apoptosis-resistant sublines of the LNCaP human prostate cancer (CaP) cell line. Here, we assess...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

We show that the recently constructed complete and ''minimal'' third-order meson-baryon effective chiral Lagrangian can be further reduced from 84 to 78 independent operators. (orig.)

Energy Technology Data Exchange (ETDEWEB)

Comprised of seven persons with extensive experience in the issues of nuclear waste, the Independent Review Committee (IRC) provides independent and objective review of Defense Transuranic Waste Program (DTWP) activities managed by the Joint Integration Office (JIO), formerly the Defense Transuranic Waste Lead Organization (TLO). The Committee is ensured a broad, interdisciplinary perspective since its membership includes representatives from the fields of nuclear engineering, nuclear waste transportation, industrial quality control, systems and environmental engineering and state and local government. The scope of IRC activities includes overall review of specific TLO plans, projects and activities, and technical review of particular research and development projects. The Committee makes specific suggestions and recommendations based upon expertise in the field of TRU Waste Management. The IRC operates as a consulting group, under an ...

UK PubMed Central (United Kingdom)

Peptic ulcer bleeding is a common disease and recurrent bleeding is an independent risk factor of mortality. Infusion with proton pump inhibitors (PPIs) prevents recurrent bleeding after successful...Full Text Available

UK PubMed Central (United Kingdom)

IL-4 and IL-13 are up-regulated during in vivo responses to many nematode parasites, but increasing evidence suggests that increases in IL-13 can also occur independently of...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

It is shown that a relativistic point kinematics with one independent dilation of (scalar) proper time for each spatial freedom degree would give a really rigorous physical significance to the ordinary logical resolution of the clock paradox between systems in relative motion.

UK PubMed Central (United Kingdom)

B lymphocytes can function independently as efficient APCs. However, our previous studies demonstrate that both dendritic cells and macrophages are necessary to propagate immune responses initiated...Full Text Available

UK PubMed Central (United Kingdom)

We sequenced 16S rRNA genes from the vaginal swab contents of a postmenopausal woman with asymptomatic bacterial vaginosis (BV). Sequences from Atopobium vaginae were the most commonly...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The scattering of a charged scalar field on Coulomb potential on de Sitter space-time is studied using the solution of the free Klein-Gordon equation. We find that the scattering amplitude is independent of the choice of the picture and in addition the total energy is conserved in the scattering process.

UK PubMed Central (United Kingdom)

Recently, CID755673 was reported to act as a highly selective inhibitor of protein kinase D (PKD). In the course of experiments using CID755673, we noticed that it exerted unexpected stimulatory...Full Text Available

UK PubMed Central (United Kingdom)

Several independent studies of bacterial degradation of nitrate ester explosives have demonstrated the involvement of flavin-dependent oxidoreductases related to the old yellow enzyme (OYE) of yeast....Full Text Available

UK PubMed Central (United Kingdom)

We used tryptophan auxotrophs of the dicot Arabidopsis thaliana (wall cress) to determine whether tryptophan has the capacity to serve as a precursor to the auxin, indole-3-acetic acid (IAA). Quantitative...Full Text Available

UK PubMed Central (United Kingdom)

Decreased cognitive performance reduces independence and quality of life for aging individuals. Healthy brain aging does not involve significant neuronal loss, but little is known about the...Full Text Available

Science.gov (United States)

...retardation, behavioral disorders or...blood. (3) Health protection goals...protecting your health. You are strongly...an independent analysis. The two...impairment of health. One of...although most cases of lead-induced...in the form of behavioral...

Energy Technology Data Exchange (ETDEWEB)

Nitrite is to be used to inhibit pitting corrosion during Extended Sludge Processing (ESP) at the Savannah River Plant. The required nitrite concentrations are expressed as a function of the slurries' nitrate ion concentration and temperature. In the most dilute slurries, the nitrite inhibitor requirement is independent of the nitrate ion concentration and depends only on the temperature of the waste. The nitrate-independent concentration ensures that there is sufficient inhibitor, in sludge slurries whose nitrate has been depleted by radiolysis, to prevent pitting corrosion induced by other corrosive anions (e.g., sulfate and chloride). The threshold nitrate concentration at which the nitrite level is expressed as a function only of temperature is 0.02 M.

International Nuclear Information System (INIS)

Experimental differential cross sections for 104 MeV #alpha#-particle scattering have been analysed using a method recently proposed for model-independent analyses. Reliable values of isoscalar (0"+ -3"1"-) octupole transition rates in _5_0Ti, _5_2Cr and _2_0_8Pb are presented and compared with electromagnetic rates. (author).

Energy Technology Data Exchange (ETDEWEB)

This report presents the results of the 2003 Radiological Environmental Monitoring Program conducted in accordance with 10 CFR 72.44 for the Fort St. Vrain Independent Spent Fuel Storage Installation. A description of the facility and the monitoring program is provided. The results of monitoring the predominant radiation exposure pathway, direct radiation exposure, indicate the facility operation has not contributed to any increase in the estimated maximum potential dose commitment to the general public.

UK PubMed Central (United Kingdom)

BackgroundMany commercial banana varieties lack sources of resistance to pests and diseases, as a consequence of sterility and narrow genetic background. Fertile wild relatives,...Full Text Available

Science.gov (United States)

Students get a background on Stem Cell technology and learn to write an effective opinion essay.

Science.gov (United States)

Before working at JPL he was the Chief Engineer for the Milstar Satellite Avionics and several Military space programs. His technical background is in ...

International Nuclear Information System (INIS)

Continuum events represent an eminent source of background in any e+e- experiment. As these have a higher branching ratio than BB-bar events (at BaBar this ratio is estimated to about 3.5) or ?+?- events, efficient continuum background suppression is essential in many analyses. Using Artificial Neural Networks and the Nearest Neighbor Method we developed several selectors which, based only on the global event shape variables, efficiently tag BB-bar events and ?+?- events against the continuum background. These selectors could then be combined with the channel specific information in various types of analyses. The study was done using a parametric Monte Carlo.

Energy Technology Data Exchange (ETDEWEB)

Properties of the multi-species electromagnetic Weibel and electrostatic two-stream instabilities are investigated for an intense ion beam propagating through background plasma. Assuming that the background plasma electrons provide complete charge and current neutralization, detailed linear stability properties are calculated within the framework of a macroscopic cold-fluid model for a wide range of system parameters.

Energy Technology Data Exchange (ETDEWEB)

The existence of a cosmic neutrino background - the analogue of the cosmic microwave background - is a fundamental prediction of standard big bang cosmology. Up to now, the observational evidence for its existence is rather indirect and rests entirely on cosmological observations of, e.g., the light elemental abundances, the anisotropies in the cosmic microwave background, and the large scale distribution of matter. Here, we review more direct, weak interaction based detection techniques for the cosmic neutrino background in the present epoch and in our local neighbourhood. We show that, with current technology, all proposals are still off by some orders of magnitude in sensitivity to lead to a guaranteed detection of the relic neutrinos. The most promising laboratory search, based on neutrino capture on beta decaying nuclei, may be done in future experiments designed to measure the neutrino mass ...

Energy Technology Data Exchange (ETDEWEB)

This lectures aim at giving graduate students an introduction to a working knowledge of path integral methods in a wide variety of fields in physics. Consequently, the the lecture notes are organized in three main parts dealing with non-relativistic quantum mechanics, many-body physics and field theory. In the first part the basic concepts of path integrals are developed in the usual heuristic, non-mathematical way followed by the standard examples of quadratic Lagrangians for which the path integrals can be solved exactly. Applications include semi-classical expansions, scattering problems and the representation of Green functions as path integrals. In the last chapter of this part it is shown how (euclidean) path integrals can be treated numerically by Monte-Carlo methods with a program for the anharmonic oscillator as an explicit example. The second part deals with the application of path integrals in statistical mechanics and many-body problems. Various chapters treat the partition ...

Science.gov (United States)

The Milstar communications satellite system will provide secure antijam communication capabilities for DOD operations into the next century. In order to accomplish this task, the Milstar system will employ precise timekeeping on its satellites and at its ground control stations. The constellation will consist of four satellites in geosynchronous orbit, each carrying a set of four rubidium (Rb) atomic clocks. Several times a day, during normal operation, the Mission Control Element (MCE) will collect timing information from the constellation, and after several days use this information to update the time and frequency of the satellite clocks. The MCE will maintain precise time with a cesium (Cs) atomic clock, synchronized to UTC(USNO) via a GPS receiver. We have developed a Monte Carlo simulation of Milstar's space segment timekeeping. The simulation includes the effects of: uplink/downlink time transfer noise; satellite crosslink time transfer noise; satellite diurnal temperature ...

Science.gov (United States)

The galvanomagnetic properties of single-crystal samples of the Bi{sub 0.93}Sb{sub 0.07} semiconductor alloy with the electron density n = 1.6 x 10{sup 17} cm{sup -3} in magnetic fields up to 14 T at T = 1.6 K have been investigated. The resistivity {rho} and Hall coefficient R have been measured as functions of the magnetic field directed along the binary axis of a crystal for a current flowing through a sample along the bisector axis; i.e., the components {rho}{sub 22} and R{sub 32,1} have been measured. The strong anisotropy of the electron spectrum of the samples makes it possible to separately observe quantum oscillations of the magnetoresistance {rho}{sub 22}(H) for H -parallel C{sub 2} in low magnetic fields for two equivalent ellipsoids with small extremal cross sections (secondary ellipsoids) and in high magnetic fields for electrons of the ellipsoid with a large extremal cross section (main ellipsoid). An increase in the energy of the electrons of secondary ellipsoids in the ...

International Nuclear Information System (INIS)

Complete calculations of the accelerator related background in the muon spectrometer of the CMS detector at the Large Hadron Collider are presented. The simulations have been performed with the STRUCT multi-turn tracking code and the MARS and FLUKA cascade codes taking into account latest information of the LHC lattice, vacuum conditions, beam cleaning system and the shielding and layout of the CMS experiment. Beam loss distributions in the interaction regions and their vicinities and their contribution to the background levels in the muon spectrometer of CMS are analyzed. The studies show that hadronic and electromagnetic components of machine background are efficiently suppressed by the proposed CMS shielding. High energy muons penetrate through the shielding, but in positions of significance they do not contribute more than a few percent compared to the background generated by the pp-collisions. It ...

CERN Document Server

We consider a general, neutral, dynamical model of biodiversity. Individuals have i.i.d. lifetime durations, which are not necessarily exponentially distributed, and each individual gives birth independently at constant rate \\lambda. We assume that types are clonally inherited. We consider two classes of speciation models in this setting. In the immigration model, new individuals of an entirely new species singly enter the population at constant rate \\mu (e.g., from the mainland into the island). In the mutation model, each individual independently experiences point mutations in its germ line, at constant rate \\theta. We are interested in the species abundance distribution, i.e., in the numbers, denoted I_n(k) in the immigration model and A_n(k) in the mutation model, of species represented by k individuals, k=1,2,...,n, when there are n individuals in the total population. In the immigration model, we prove that the numbers (I_t(k);k\\ge 1) ...

Energy Technology Data Exchange (ETDEWEB)

We suggest and describe the use of a binary pseudo-random (BPR) grating as a standard test surface for measurement of the modulation transfer function (MTF) of interferometric microscopes. Knowledge of the MTF of a microscope is absolutely necessary to convert the measured height distribution of a surface undergoing metrology into an accurate power spectral density (PSD) distribution. For an'ideal' microscope with an MTF function independent of spatial frequency out to the Nyquist frequency of the detector array with zero response at higher spatial frequencies, a BPR grating would produce a flat 1D PSD spectrum, independent of spatial frequency. For a'real' instrument, the MTF is found as the square root of the ratio of the PSD spectrum measured with the BPR grating to the'ideal,' spatial frequency independent, PSD spectrum. We present the results from a measurement of the MTF ...

International Nuclear Information System (INIS)

Using a noneikonal expression for the two-body scattering amplitude, consistent with the proton-nucleon scattering data, the cross-section of the 1.04 GeV-proton elastic scattering on "4"0Ca is calculated by the Glauber-Sitenko theoretical scheme in the framework of the coherent density fluctuation model (CDFM) as well as of the independent-particle model (IPM). It is shown that the use of the noneikonal amplitude in the CDFM calculations improves the agreement with the experimental data especially at larger scattering angles in contrast to the case of the independent-particle model. To that end a decisive role play the zero-motion flucton correlations taken into account in the CDFM. (orig.).

DEFF Research Database (Denmark)

In this work, we address the problem of road interpretation for driver assistance based on an early cognitive vision system. The structure of a road and the relevant traf?c are interpreted in terms of ego-motion estimation of the car, independently moving objects on the road, lane markers and large scale maps of the road. We make use of temporal and spatial disambiguation mechanisms to increase the reliability of visually extracted 2D and 3D information. This information is then used to interpret the layout of the road by using lane markers that are detected via Bayesian reasoning. We also estimate the ego-motion of the car which is used to create large scale maps of the road and also to detect independently moving objects. Sample results for the presented algorithms are shown on a stereo image sequence, that has been collected from a structured road.

International Nuclear Information System (INIS)

A new controlled-clearance pressure balance is under development with the aim of improving the hydraulic high-pressure standard up to 1 GPa. This pressure balance consists of three parts: (i) a pressure generation device up to 1 GPa, (ii) a weight-loading unit which can load/unload weights automatically and independently, (iii) a controlled-clearance piston-cylinder which is designed to allow the jacket pressure to be applied independently. Some adjustments were made for loading heavy weights on/off the piston safely, keeping them in balance, then generating the pressure stably. Stability of the generated pressure was checked for several piston-cylinders, and it was found that pressure fluctuation was less than a few parts per million. The jacket pressure coefficient of a 500 MPa controlled-clearance piston-cylinder was precisely evaluated as a function of both the system pressure and the jacket pressure.

British Library Electronic Table of Contents (United Kingdom)

Independent component analysis (ICA), an efficient higher order statistics (HOS) based blind source separation technique, has been successfully applied in various fields. In this paper, we provide an overview of the applications of ICA in multiple-input multiple-output (MIMO) wireless communication systems, and introduce some of the important issues surrounding them. First, we present an ICA based blind equalization scheme for MIMO orthogonal frequency division multiplexing (OFDM) systems, with linear precoding for ambiguity elimination. Second, we discuss three peak-to-average power ratio (PAPR) reduction schemes, which do not introduce any spectral overhead. Third, we investigate the application of ICA to blind compensation for inphase/quadrature (I/Q) imbalance in MIMO OFDM systems. Fin...

British Library Electronic Table of Contents (United Kingdom)

To test whether the dose addition and independent action models can predict the combined toxicity of the mixtures of phenol and aniline derivatives, six phenolic and two aniline derivatives were selected as the test components. The inhibition toxicity of the derivatives and their mixtures to Vibrio qinghaiensis sp.-Q67 indicated that all dose?response relationships could be effectively described by the Weibull function with correlation coefficients greater than 0.99. The combined toxicity of two equivalent-effect concentration ratio mixtures and eight uniform design concentration ratio mixtures could be predicted successfully by the dose addition model within 95% confidence intervals. However, it was also well predicted by the independent action model, especially at lower concentrations.

Science.gov (United States)

A model is presented for describing the Amputee Independent Prosthesis Properties (AIPP) of complete assemblies of trans-tibial prosthetic components distal to the socket. This new AIPP model includes features of both lumped parameter and roll-over models and describes prosthesis properties that are of importance in stance phase, including prosthetic foot geometry, normal stiffness, shear stiffness, and damping (energy dissipation). Methods are described for measuring the parameters of the AIPP model using a custom test-rig, commercial load-cell, and a motion capture system. Example data are presented for five pylon angles reflecting the shank angles seen in normal gait. Through the inclusion of measured AIPP in future in-vivo studies comparing different prostheses more generic information, as opposed to product specific claims, will become more widely available to inform future designs, prescription, and alignment procedures. PMID:21831379

British Library Electronic Table of Contents (United Kingdom)

Experiments based on a 23 central composite full factorial design were carried out in 200-ml stainless-steel containers to study the pretreatment, with dilute sulfuric acid, of a sugarcane bagasse sample obtained from a local sugar?alcohol mill. The independent variables selected for study were temperature, varied from 112.5?C to 157.5?C, residence time, varied from 5.0 to 35.0 min, and sulfuric acid concentration, varied from 0.0% to 3.0% (w/v). Bagasse loading of 15% (w/w) was used in all experiments. Statistical analysis of the experimental results showed that all three independent variables significantly influenced the response variables, namely the bagasse solubilization, efficiency of xylose recovery in the hemicellulosic hydrolysate, efficiency of cellulose enzymatic saccharificatio...

CERN Document Server

It has been proposed that a hidden conformal field theory (CFT) governs the dynamics of low frequency scattering in a general Kerr black hole background. We further investigate this correspondence by mapping higher order corrections to the massless wave equations in a Kerr background to an expansion within the CFT in terms of higher dimension operators. This implies the presence of infinite towers of CFT primary operators with positive conformal dimensions compatible with unitarity. The exact Kerr background softly breaks the conformal symmetry and the scaling dimensions of these operators run with frequency. The scale-invariant fixed point is dual to a degenerate case of flat spacetime.

UK PubMed Central (United Kingdom)

BackgroundDuplications of stretches of the genome are an important source of individual genetic variation, but their unrecognized presence in laboratory organisms would be a confounding...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundThe WINPEPI computer programs for epidemiologists are designed for use in practice and research in the health field and as learning or teaching aids. The programs are free,...Full Text Available

UK PubMed Central (United Kingdom)

Background. The role of vitamin D in the body's ability to fight influenza and URI's may be dependent on regulation of specific cytokines that participate in the host inflammatory...Full Text Available

CERN Document Server

A new estimator of the local density of dark energy is suggested which comes from the virial theorem for non-relativistic gravitating systems embedded in the uniform dark energy background.

UK PubMed Central (United Kingdom)

BackgroundThe endoscopic endonasal transsphenoidal approach (EETA) to the pituitary is performed by ear, nose, and throat (ENT) surgeons in collaboration with neurosurgeons but also...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundIncrease in the incidence of hyperuricemia associated with gout as well as hypertension, renal diseases and cardiovascular diseases has been a public health concern. We...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundLate-onset sepsis in the premature infant is frequently revealed by severe, unusual and recurrent bradycardias. In view of the high morbidity and mortality...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundSister species divergence and reproductive isolation commonly results from ecological adaptation. In mimetic Heliconius butterflies, shifts in colour pattern...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundOver the past decade, many investigators have used sophisticated time series tools for the analysis of genomic sequences. Specifically, the correlation of the nucleotide...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundDiscrepancies between the conclusions of different meta-analyses (quantitative syntheses of systematic reviews) are often ascribed to methodological differences. The objective...Full Text Available

UK PubMed Central (United Kingdom)

Background:To encourage evidence-based practice, an Annals of Internal Medicine editorial called for a new professional on clinical teams: an informationist trained...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundLow back pain (LBP) is the most prevalent musculoskeletal condition and one the most common causes of disability in the developed nations. Anecdotally, there is a general...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundThe availability of multiple, essentially complete genome sequences of prokaryotes and eukaryotes spurred both the demand and the opportunity for the construction of an...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundUnderstanding the mechanisms that control rates of disease progression in humans and other species is an important area of research relevant to epidemiology and to translating...Full Text Available

UK PubMed Central (United Kingdom)

Background:Prolonged mechanical ventilation is increasingly common. It is expensive and associated with significant morbidity and mortality. Our objective is to comprehensively characterize...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundElementary schools represent both a source of childhood sun exposure and a setting for educational interventions.MethodsSun Protection...Full Text Available

UK PubMed Central (United Kingdom)

Background:Solid pseudopapillary tumor is a rare pancreatic neoplasm with uncertain to low malignant potential. This is an uncommon neoplasm with many pseudonyms, occurring...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundABCA3 transporter (ATP-binding cassette transporter of the A subfamily) is localized to the limiting...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundTo identify the differential tuberculosis (TB) characteristics within the immigrant population with respect to natives in Spain.Methodology/Principal...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundAlternative splicing is an important mechanism mediating the diversified functions of genes in multicellular organisms, and such event occurs in around 40-60% of human...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundNonsteroidal anti-inflammatory drugs are commonly used to treat postoperative and chronic pain. Animal studies suggest these drugs act in part by blocking...Full Text Available

UK PubMed Central (United Kingdom)

Background The Internet is becoming an increasingly important resource for health-information seekers. However, consumers often do not use effective search...Full Text Available

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BackgroundBrucellosis is a zoonosis of veterinary, public health and economic significance in most developing countries. Human brucellosis is a severely debilitating disease that...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundWhether psychological resilience correlates with neurocognitive performance is largely unknown. Therefore, we assessed association between neurocognitive...Full Text Available

UK PubMed Central (United Kingdom)

Background/AimTo assess pathophysiology in irritable bowel syndrome (IBS).Methods122 IBS patients...Full Text Available

UK PubMed Central (United Kingdom)

Background/Aim:To assess the prognostic indicators preoperatively presenting and influencing the mortality rate following esophagectomy for esophageal cancer.Full Text Available

UK PubMed Central (United Kingdom)

BackgroundStatistical autoregressive analyses of direct and delayed density dependence are widespread in ecological research. The models suggest that changes in ecological factors...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundBisphenol A (BPA) is a high-production-volume chemical commonly used in the manufacture of polycarbonate plastic. Low-level concentrations of BPA in animals and possibly...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundPlasmodium falciparum is the most malignant agent of human malaria. It belongs to the taxon Laverania, which includes other ape-infecting Plasmodium...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundPhotorhabdus luminescens is a Gram-negative luminescent enterobacterium and a symbiote to soil nematodes belonging to the species Heterorhabditis...Full Text Available

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OBJECTIVE: New surgical procedures designed to assist in the treatment of peritoneal surface malignancy were sought. BACKGROUND: Decisions regarding the treatment of cancer depend on the anatomic location...Full Text Available

UK PubMed Central (United Kingdom)

Background:Percutaneous tracheostomy (PT) has gained an increasing acceptance as an alternative to the conventional surgical tracheostomy (ST). In experienced hands, and with...Full Text Available

UK PubMed Central (United Kingdom)

BACKGROUND:In adults, it is well known that high levels of pain catastrophizing are related to increased pain and disability as well as to heightened anxiety and depression. However,...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundGenetic predisposition to scrapie in sheep is associated with several variations in the peptide sequence of the prion protein gene (PRNP). DNA-based tests...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundTitanium and titanium alloys are widely used for fabrication of dental implants. Since the material composition and the surface topography of a biomaterial play a fundamental...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundPrior research links optimism to physical health, but the strength of the association has not been systematically evaluated.PurposeFull Text Available

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BackgroundSoft tissue foreign bodies are a common cause of orthopedic consultation in emergency departments. It is difficult to confirm their existence because conventional radiology...Full Text Available

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BackgroundMovement regularities are inherently present in automated goal-directed motions of the primate's arm system. They can provide important signatures of intentional behaviours...Full Text Available

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BackgroundThe ongoing epidemiological transition in Mexico minimizes the relative impact of neurocysticercosis (NC) on public health. However, hard data on the disease frequency...Full Text Available

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Background and PurposeHemodynamic insults at arterial bifurcations are hypothesized to play a key role in intracranial aneurysm formation. This study investigates...Full Text Available

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ObjectivesWe sought to identify a novel gene for dilated cardiomyopathy (DCM).BackgroundDCM is a heritable, genetically...Full Text Available

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BackgroundStump and phantom pains are debilitating sequelae of amputations that are often resistant to treatment. The efficacy of pharmacologic therapies, including...Full Text Available

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BackgroundMolecular genetic studies of Bombyx mori have led to profound advances in our understanding of the regulation of development. Bombyx mori brain,...Full Text Available

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Background: Contamination of autologous grafts unfortunately occurs in plastic surgery, but the literature provides no guidance for management of such incidents. Methods: American...Full Text Available

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BackgroundMalaria is one of the most important tropical diseases that affects people globally. The influence of environmental conditions in the patterns of temporal distribution...Full Text Available

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BackgroundAlthough local excision (ampullectomy) was first described by Halsted in 1899, its adequacy as an alternative surgical treatment for the ampullary tumors is still a matter...Full Text Available

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Background and AimsIt is well known that genome size differs among species. However, information on the variation and dynamics of genome size in wild populations and on the early...Full Text Available

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BackgroundFloating knee injuries are usually associated with other significant injuries. Do these injuries have implications on the management of the floating knee and the final...Full Text Available

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• Background and Aims The occurrence of stomata in seed coats is uncommon and there is limited information about their function(s). The aim of this study was to verify the distribution...Full Text Available

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BackgroundWhereas there is increasing evidence that loss of expression and/or function of the thyroid hormone receptors (TRs) could result in a selective advantage for tumor development,...Full Text Available

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BackgroundIn biomedical ontologies, mereological relations have always been subject to special interest due to their high relevance in structural descriptions of anatomical entities,...Full Text Available

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BackgroundRecent studies have shown associations between size and body proportions at birth and health outcomes throughout the life cycle, but there are few data...Full Text Available

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BackgroundThe use of fractionated stereotactic radiotherapy (fsrt) has evolved with technical advances in noninvasive immobilization, radiation delivery, and image guidance....Full Text Available

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Background and AimsAnnonaceae are one of the largest families of Magnoliales. This study investigates the comparative floral development of 15 species to understand the basis for...Full Text Available

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BackgroundSenescence is integral to the flowering plant life-cycle. Senescence-like processes occur also in non-angiosperm land plants, algae and photosynthetic prokaryotes. Increasing...Full Text Available

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BackgroundEnzyme-linked immunosorbent assay (ELISA) is a standard immunoassay to estimate a protein's concentration in a sample. Deploying ELISA in a microarray format permits simultaneous...Full Text Available

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This article examines how politics and science interacted against a background of uncertainty to shape policy in the case of environmental contamination by polybrominated biphenyls (PBB) in Michigan....Full Text Available

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Background:Since first reported in 1996, endoscopic minimally invasive surgery of the cervical region has been shown to be safe and effective in the treatment of benign thyroid and...Full Text Available

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Background:People with severe and persistent mental illness need help in most aspects of their lives, as the disability associated with these diseases can be debilitating....Full Text Available

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BackgroundWomen with fecal incontinence (FI) and rectal urgency have increased rectal stiffness and sensation.AimsTo...Full Text Available

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BackgroundThe aim of this report was to describe duodenal obstruction caused by a rubber foreign body in a cow.Case PresentationThe clinical, biochemical...Full Text Available

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BackgroundPerfluoroalkyl acids (PFAAs) are found globally in wildlife and humans and are suspected to act as endocrine disruptors. There are no previous reports of PFAA levels in...Full Text Available

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Does the cultural background influence the success with which genetically unrelated individuals cooperate in social dilemma situations? In this paper, we provide an answer by analysing the data of Full Text Available

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BackgroundInternet-based depression communities provide a forum for individuals to communicate and share information and ideas. There has been little research into the health status...Full Text Available

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BackgroundClostridium botulinum produces seven distinct serotypes of botulinum neurotoxins (BoNTs). The genes encoding different subtype neurotoxins of serotypes...Full Text Available

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BackgroundHypertension is a common non communicable condition worldwide. In developing countries (including Nigeria), the use of complementary and alternative medicine (CAM) is common....Full Text Available

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BackgroundNucleotide sequences and the gene arrangements of mitochondrial genomes are effective tools for resolving phylogenetic problems. Hemipteroid insects are known to possess...Full Text Available

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Background:Children of people with alcohol dependence (COAs) are at high risk for behavioral and cognitive problems.Aim:Aim of...Full Text Available

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Background:Cemented hip arthroplasty is an established treatment for femoral neck fracture in the mobile elderly. Cement pressurization raises intramedullary pressure and...Full Text Available

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BackgroundCystinuria is the most common inherited cause of urinary tract stones in children. It can lead to obstructive uropathy, which is a major cause of renal...Full Text Available

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BackgroundOsseointegration is crucial for the long-term success of dental implants and depends on the tissue reaction at the tissue-implant interface. Mechanical properties and biocompatibility...Full Text Available

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BackgroundMeasures of attachment style are often used to appraise social and emotional health. In developmental literature, the concept of attachment is used to explain...Full Text Available

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BackgroundArtificial duplicates from pyrosequencing reads may lead to incorrect interpretation of the abundance of species and genes in metagenomic studies. Duplicated reads were...Full Text Available

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BackgroundThe aim of this study was to investigate the anticancer activity and mechanism of action of Noscapine alone and in combination with Doxorubicin against triple negative...Full Text Available

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BackgroundArtocarpus communis is used traditionally in Cameroon to treat several ailments, including infectious and associated diseases. This work was therefore...Full Text Available

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BackgroundHearing loss is a common sensory disorder, yet prospective data on potentially modifiable risk factors are limited. Regularly used analgesics, the most...Full Text Available

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Background:Antimicrobial agents have been used as a chemotherapeutic agent to improve oral health. This in vitro study was carried out to determine the antimicrobial activity...Full Text Available

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Background/Objectives:Imaging technology is an important part of the diagnosis and management of spinal trauma. Indications and findings in post-traumatic imaging of the vertebral...Full Text Available

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Background:Alopecia areata (AA) is an immune-mediated form of hair loss that occurs in all ethnic groups, ages, and both sexes. Helicobacter pylori has...Full Text Available

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BackgroundMultilevelness is a defining characteristic of complex systems. For example, in the intestinal tissue the epithelial lining is organized into crypts that are maintained...Full Text Available

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BackgroundThe permeabilization of mitochondrial membranes is a decisive event in apoptosis or necrosis culminating in cell death. One fundamental mechanism by which...Full Text Available

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BackgroundMany difficult problems in evolutionary genomics are related to mutations that have weak effects on fitness, as the consequences of mutations with large effects are often...Full Text Available

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